Ground Water

Question 1

What is an infiltration gallery?

Answer 1

A horizontal drain made from open jointed or perforated pipes or a block drain which is laid below the water tables and collects ground water.

Infiltration galleries are essential for managing groundwater resources.

Question 2

What type of soil is required for an infiltration gallery?

Answer 2

Soils that are permeable to allow sufficient water to be collected.

Permeability is crucial for the effectiveness of the infiltration gallery.

Question 3

What surrounds an infiltration gallery to improve flow and filter particles?

Answer 3

A gravel (filter) pack.

The gravel pack helps in enhancing the efficiency of water collection.

Question 4

How do infiltration galleries collect water from rivers?

Answer 4

They collect subsurface flow from rivers and transport it to a collection well or sump.

This method helps in utilizing natural water sources effectively.

Question 5

What can be done with water collected in an infiltration gallery?

Answer 5

It can be withdrawn directly or pumped to a storage tank.

This flexibility allows for better water management.

Question 6

True or False: Infiltration galleries can only be used as a standalone water supply.

Answer 6

False.

They are often used in conjunction with other water supplies to increase water quantity.

Question 7

Fill in the blank: An infiltration gallery is laid below the _______ to collect ground water.

Answer 7

water tables.

Question 8

What are infiltration wells?

Answer 8

Wells sunk in series in the banks of a river to obtain large quantities of water.

Question 9

How are infiltration wells designed?

Answer 9

Closed at the top, open at the bottom with manholes for inspection.

Question 10

What is the purpose of the bottom opening in infiltration wells?

Answer 10

Allows water to infiltrate through sand beds, resulting in some purification.

Question 11

What connects infiltration wells to the collecting sump?

Answer 11

Porous pipes.

Question 12

What is a jack well?

Answer 12

A collecting sump connected to infiltration wells.

Question 13

What forms a spring?

Answer 13

Underground water appearing at the surface.

Question 14

Why are springs significant for small towns?

Answer 14

They serve as sources of water supply, especially near hills.

Question 15

What can cause some springs to discharge hot water?

Answer 15

The presence of minerals such as nhur.

Question 16

Can hot springs be used for regular water supply?

Answer 16

No, they are not suitable for regular supply but may cure some human disorders.

Question 17

What are the three types of springs?

Answer 17

Gravity, artesian, and another unspecified type.

Question 18

Fill in the blank: Infiltration wells are connected by ______ to a collecting sump.

Answer 18

porous pipes

Question 19

True or False: All springs discharge cold water.

Answer 19

False

Question 20

What are the three types of springs?

Answer 20

• Gravity
• Artesian
• Surface

Types of springs categorized based on their formation and characteristics.

Question 21

What characterizes gravity springs?

Answer 21

Develop due to overflowing of the water table

Yield varies with the position of the water table, which can fluctuate with rainfall.

Question 22

What can happen to gravity springs during dry seasons?

Answer 22

They can dry up

This is due to the variability in the water table influenced by rainfall.

Question 23

What forms artesian springs?

Answer 23

Presence of fissure or crack in an impervious layer

The fissure must extend to the ground surface.

Question 24

What is a key feature of artesian springs?

Answer 24

They provide a practically uniform quantity of water throughout the year

This consistency is due to the nature of the fissure in the impervious layer.

Question 25

How are surface springs formed?

Answer 25

When subsoil water is exposed to the ground surface by an impervious layer ## Footnote The obstruction created by the impervious layer allows the water to surface.

Question 26

What is a water-bearing ground formation?

Answer 26

A geological formation that can hold and transmit groundwater ## Footnote It is crucial for the development of springs and wells.

Question 27

Define impervious layer.

Answer 27

A layer that does not allow water to pass through ## Footnote This layer is important in groundwater management.

Question 28

What is the groundwater table?

Answer 28

The upper surface of the zone of saturation where groundwater pressure is equal to atmospheric pressure ## Footnote It indicates the level below which the ground is saturated with water.

Question 29

What is a spring?

Answer 29

A natural source of water that flows from the ground ## Footnote Springs often form where the groundwater table intersects the land surface.

Question 30

List the qualities of spring water.

Answer 30

* Clear * Bright * Palatable ## Footnote The quality can vary based on geological and topographical conditions.

Question 31

What factors affect the quality of spring water?

Answer 31

* Geological conditions * Topographical conditions ## Footnote Other factors include pollution and mineral content.

Question 32

What are the potential characteristics of spring water?

Answer 32

* Hard or soft * Pure or polluted * Saline or sulphurous ## Footnote The characteristics depend on the surrounding environment and geology.

Question 33

What is a well?

Answer 33

An artificial hole or pit made in the ground for tapping water ## Footnote Wells can be accessed manually or through pumps.

Question 34

Name the types of wells.

Answer 34

* Shallow wells * Deep wells * Tube wells * Artesian wells ## Footnote Each type serves different depths and purposes for water extraction.

Question 35

What is the typical yield of springs?

Answer 35

Mostly inadequate except for small supplies ## Footnote Springs can vary greatly in yield based on their location and geological structure.

Question 36

Fill in the blank: The spring water which is not disturbed by rainfall is usually _______.

Answer 36

attractive in appearance and of good palatability

Question 37

What makes spring water sparkle?

Answer 37

The gases it contains ## Footnote This is often a characteristic of high-quality spring water.

Question 38

Why is deep spring water often very hard?

Answer 38

It contains an excess of salts ## Footnote This is a common characteristic of water sourced from deeper geological formations.